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Check if string contains dash and add double quotes to the word

I would like to detect if string contains dash and add double quotes at the beginning of word and at the end of the word. If there is only a dash we should skip it. Also, the word with dash should be replaced if contains only numbers.
Input: test-dash - good example 123-123
Output: test-dash - good example "123-123"
So far I have REGEX like \S*[0-9]+\S* but it matches 7 places.
Language: C#
Update: current version: https://regex101.com/r/RKgDXE/1

Just use Regex.Replace method with pattern: (\d+-\d+)
Pattern explanation:
(...) - capturing group
\d+ - match one ore more digits
- - match dash literally
Code sample:
var parsedString = Regex.Replace("test-dash - good example 123-123", #"(\d+-\d+)", "\"$1\"");

Try following code:
string pattern = #"\d+[-]\d+$";
string input = "test-dash - good example 123-123";
string output = Regex.Match(input, pattern).Value;
Console.WriteLine(input.Replace(output, string.Format("\"{0}\"", output)));
// output
// test-dash - good example "123-123"

Regex first digits occurrence

My task is extract the first digits in the following string:
GLB=VSCA|34|speed|1|
My pattern is the following:
(?x:VSCA(\|){1}(\d.))
Basically I need to extract "34", the first digits occurrence after the "VSCA". With my pattern I obtain a group but would be possibile to get only the number? this is my c# snippet:
string regex = #"(?x:VSCA(\|){1}(\d.))";
Regex rx = new Regex(regex);
string s = "GLB=VSCA|34|speed|1|";
if (rx.Match(s).Success)
{
var test = rx.Match(s).Groups[1].ToString();
}

You could match 34 (the first digits after VSCA) using a positive lookbehind (?<=VSCA\D*) to assert that what is on the left side is VSCA followed by zero or times not a digit \D* and then match one or more digits \d+:
(?<=VSCA\D*)\d+
If you need the pipe to be after VSCA the you could include that in the lookbehind:
(?<=VSCA\|)\d+
Demo

This regex pattern: (?<=VSCA\|)\d+?(?=\|) will match only the number. (If your number can be negative / have decimal places you may want to use (?<=VSCA\|).+?(?=\|) instead)

You don't need Regex for this, you can simply split on the '|' character:
string s = "GLB=VSCA|34|speed|1|";
string[] parts = s.Split('|');
if(parts.Length >= 2)
{
Console.WriteLine(parts[1]); //prints 34
}
The benefit here is that you can access all parts of the original string based on the index:
[0] - "GLB=VSCA"
[1] - "34"
[2] - "speed"
[3] - "1"
Fiddle here

While the other answers work really well, if you really must use a regular expression, or are interested in knowing how to get to that straight away you can use a named group for the number. Consider the following code:
string regex = #"(?x:VSCA(\|){1}(?<number>\d.?))";
Regex rx = new Regex(regex);
string s = "GLB:VSCA|34|speed|1|";
var match = rx.Match(s);
if(match.Success) Console.WriteLine(match.Groups["number"]);

How about (?<=VSCA\|)[0-9]+?
Try it out here

Splitting of a string using Regex

I have string of the following format:
string test = "test.BO.ID";
My aim is string that part of the string whatever comes after first dot.
So ideally I am expecting output as "BO.ID".
Here is what I have tried:
// Checking for the first occurence and take whatever comes after dot
var output = Regex.Match(test, #"^(?=.).*?");
The output I am getting is empty.
What is the modification I need to make it for Regex?

You get an empty output because the pattern you have can match an empty string at the start of a string, and that is enough since .*? is a lazy subpattern and . matches any char.
Use (the value will be in Match.Groups[1].Value)
\.(.*)
or (with a lookahead, to get the string as a Match.Value)
(?<=\.).*
See the regex demo and a C# online demo.
A non-regex approach can be use String#Split with count argument (demo):
var s = "test.BO.ID";
var res = s.Split(new[] {"."}, 2, StringSplitOptions.None);
if (res.GetLength(0) > 1)
Console.WriteLine(res[1]);

If you only want the part after the first dot you don't need a regex at all:
x.Substring(x.IndexOf('.'))

Get only integer value from a string which contains bracket { in C#

I have a simple, very simple regex pattern like:
private static string FORMAT_REGEX = #"\{(\d)\}";
I have a string like I have {323} dollars and I want to get only 323
When I used:
Regex regex = new Regex(FORMAT_REGEX);
Match match = regex.Match(format);
if (match.Success)
{
return match.Groups[0].Value; // here comes {323} instead of 323
}
I'm sure that my pattern is wrong. What is the correct pattern ?

Only a small mistake.
You need a + sign after \d like this: \d+ to capture all digits.
And you need to get the first group: match.Groups[1].Value
Edit:
Here is a .NETFiddle

Groups[0] will always return the whole capture. You need to get the value of Groups[1].
Also, you need to capture multiple digits:
#"\{(\d+)\}";
// not
#"\{(\d)\}";
See the example at MSDN: Match.Groups Property for an example of just this, where you can capture multiple groups as well as the whole string. In that example they use \d{n} to capture exactly n digits.

Regular Expression to get all characters before "-"

How can I get the string before the character "-" using regular expressions?
For example, I have "text-1" and I want to return "text".

So I see many possibilities to achieve this.
string text = "Foobar-test";
Regex Match everything till the first "-"
Match result = Regex.Match(text, #"^.*?(?=-)");
^ match from the start of the string
.*? match any character (.), zero or more times (*) but as less as possible (?)
(?=-) till the next character is a "-" (this is a positive look ahead)
Regex Match anything that is not a "-" from the start of the string
Match result2 = Regex.Match(text, #"^[^-]*");
[^-]* matches any character that is not a "-" zero or more times
Regex Match anything that is not a "-" from the start of the string till a "-"
Match result21 = Regex.Match(text, #"^([^-]*)-");
Will only match if there is a dash in the string, but the result is then found in capture group 1.
Split on "-"
string[] result3 = text.Split('-');
Result is an Array the part before the first "-" is the first item in the Array
Substring till the first "-"
string result4 = text.Substring(0, text.IndexOf("-"));
Get the substring from text from the start till the first occurrence of "-" (text.IndexOf("-"))
You get then all the results (all the same) with this
Console.WriteLine(result);
Console.WriteLine(result2);
Console.WriteLine(result21.Groups[1]);
Console.WriteLine(result3[0]);
Console.WriteLine(result4);
I would prefer the first method.
You need to think also about the behavior, when there is no dash in the string. The fourth method will throw an exception in that case, because text.IndexOf("-") will be -1. Method 1 and 2.1 will return nothing and method 2 and 3 will return the complete string.

Here is my suggestion - it's quite simple as that:
[^-]*

This is something like the regular expression you need:
([^-]*)-
Quick tests in JavaScript:
/([^-]*)-/.exec('text-1')[1] // 'text'
/([^-]*)-/.exec('foo-bar-1')[1] // 'foo'
/([^-]*)-/.exec('-1')[1] // ''
/([^-]*)-/.exec('quux')[1] // explodes

I dont think you need regex to achieve this. I would look at the SubString method along with the indexOf method. If you need more help, add a comment showing what you have attempted and I will offer more help.

You could just use another non-regex based method. Someone gave the suggestion of using Substring, but you could also use Split:
string testString = "my-string";
string[] splitString = testString.Split("-");
string resultingString = splitString[0]; //my
See http://msdn.microsoft.com/en-US/library/ms228388%28v=VS.80%29.aspx for another good example.

If you want use RegEx in .NET,
Regex rx = new Regex(#"^([\w]+)(\-)*");
var match = rx.Match("thisis-thefirst");
var text = match.Groups[1].Value;
Assert.AreEqual("thisis", text);

Find all word and space characters up to and including a -
^[\w ]+-